On Tue, Jul 22, 2014 at 2:55 AM, Grant Edwards <invalid@invalid.invalid> wrote: > On 2014-07-21, Chris Angelico <ros...@gmail.com> wrote: >> >> When you send email, you have to have a valid envelope-from address, >> which can be found in the headers. But the From: address doesn't >> technically have to be valid. > > Note that a lot of mail servers and/or spam filters will think it's > spam if it isn't.
Yes, which is why I said "technically". Most often, a difference between envelope-from and From: header is because of a resending, like when Mailman sends mail on behalf of someone else; the From is still a valid address, but it's not the same one as the envelope-from (which will be the list-bounces address). That said, though, I've often telnetted to a mail server and done something like this: """ helo mail from:<some real address> rcpt to:<another real address> data From: me To: me Subject: Test Test! . quit """ Generally that sort of thing gets through. Sometimes it lands in a spam box, but more often it doesn't. I don't remember it ever getting rejected, other than for issues of relaying (which usually come from typoing the recipient domain). ChrisA -- https://mail.python.org/mailman/listinfo/python-list